The present invention relates to a female terminal fitting wherein a terminal main body has a shell attached to its exterior.
One example of a female terminal fitting wherein a terminal main body has a shell attached to its exterior is described in U.S. Pat. No. 5,599,212. In this example, a shell is attached to the exterior of a terminal main body provided with an electric wire contacting member and resilient contacts, this shell covering the resilient contacts. In applications using this type of female terminal fitting, one of two types of female terminal fitting can be housed within a housing: a female terminal fitting having either a tin-plated terminal main body or a gold-plated terminal main body. In signal circuits requiring a high degree of contact reliability, such as air bag circuits, the gold-plated female terminal fittings are used. In other circuits requiring a lower degree of contact reliability, tin-plated female terminal fittings are used.
Conventionally, tin-plated female terminal fittings and gold-plated terminal fittings use identical main bodies and shells. It is however somewhat difficult to visually distinguish between these identical main bodies even if they have been plated with different metals. The present invention has taken the above problem into consideration, and aims to make it possible to distinguish between a plurality of types of female terminal fittings.
According to the invention there is provided a female terminal fitting comprising a main body having a connection region for attachment to an electric wire, and a resilient contact for engaging a male terminal fitting, said terminal fitting further including a shell adapted to receive and cover said resilient contact, wherein said shell is one of a plurality of types of shells, each type of shell having a physical distinguishing feature. Such an arrangement makes it possible to distinguish visually and/or by touch between one shell and another.
Preferably each type of shell is rectangular in section and box-like, and each type of shell may have a common mouth configuration to guide a mating connector to said terminal.
The distinguishing feature may comprise one or more of the following features: the presence or absence of a protrusion, the presence or absence of an aperture in the wall of the shell, the orientation of a resilient latching arm, the position of an aperture with respect to a latching arm, the absence of an aperture in relation to a latching arm, different outer dimensions of the shells, in particular the width in relation to opposite resilient contacts.
An aperture of the shell may permit movement of a resilient contact therein, thereby permitting the terminal fitting to be narrower than if a bending space for the resilient contact was provided wholly within the shell.
The invention also provides a method of distinguishing female terminal fittings comprising a main body having a connection region for attachment to an electric wire, and a resilient contact for engaging a male terminal fitting, and a shell adapted to receive and cover said resilient contact, the method comprising the steps of providing a plurality of different types of shell, each type of shell having different physical features to permit the shell type to be distinguished.